A growing body of global research ties untreated hearing loss to an increased risk of developing dementia. So much so that, in 2017, untreated hearing loss was added to the list of major, modifiable risk factors for dementia.
Most people don’t think about untreated hearing loss as a ‘major’ risk factor for dementia. With research going on globally that demonstrates a link between untreated hearing loss and dementia, the connection is getting stronger and stronger with every study.
How does hearing loss increase the risk of dementia?
A study first published in 2017 examined the current research on the connection between hearing loss and dementia. How hearing loss increases the risk of dementia isn’t fully understood however several hypotheses have been shared.
- Hearing loss increases the load on your brain by redirecting resources to processing what is heard (or not heard) rather than thinking processes like memory.
- Hearing loss often leads to social isolation, which is also known as a dementia risk.
- There’s also some thought that there’s a common cause to both age-related hearing loss and dementia.
Another study from 2020, suggested reduced sounds getting to the brain cause the brain to stop using those areas usually engaged in interpreting sound. This may lead to those areas shrinking or degenerating, effectively altering the structure of the brain.
How big is the risk of dementia from hearing loss?
A 12-year long study at Johns Hopkins Medicine demonstrated there are actual changes in the brain when there’s hearing loss. In the study, brain scans suggested there’s increased brain atrophy when hearing loss is present. Using fMRI scans, the researchers found when the brain received a distorted or unintelligible message, whether from poor hearing or background noise interfering, the areas related to reasoning, decision-making and memory, rather than speech comprehension, were activated, essentially overloading them and making them work harder.
This same study found:
- Mild hearing loss doubled the risk of developing dementia.
- Moderate hearing loss tripled the risk of developing dementia.
- Those with severe hearing loss had a five times bigger risk of developing dementia.
What does social isolation have to do with hearing loss and dementia?
Hearing loss can isolate you from your friends and family. When you can’t hear conversations without people shouting or constantly repeating themselves, it can put a real strain on your connectivity to the world.
Social isolation is a risk for dementia so there’s a leapfrog connection with hearing loss in the middle.
A 2022 study from the University of Warwick, directly connected social isolation to changes in the areas of the brain used for memory and cognitive function.
This same study reported socially isolated people are 26% more likely to develop dementia later in life. More concerning still, the Centre for Disease Control in the United States estimates up to a 50% increase in the risk of developing dementia for those who are socially isolated.
Many people with hearing loss withdraw from social situations because of the challenges to participating actively. It may be preferable to them to withdraw rather than experience others’ frustrations with trying to communicate with them. This may be the start of social isolation and increased risk of dementia.
Do hearing aids help reduce the risk of dementia?
The research isn’t all doom and gloom. A very recent study found using hearing aids or cochlear implants reduced the risk of cognitive decline by 19% for participants with hearing loss. The study suggested the use of hearing aids can reduce the risk of developing dementia by slowing down cognitive decline, including memory loss.
Participants who already demonstrated mild cognitive decline benefited from hearing aids, in the study. It showed a 20% reduction in progressing to dementia.
With the variety of things now known to contribute to the development of dementia, including things beyond your control, it’s good to stay informed and make choices to improve your life.
Hear Well Be Well offers a free, no-obligation hearing test. Book yours today.
- Hearing loss as a risk factor for dementia: A systemic review. Rhett S. Thomson BA, Priscilla Auduong MD, Alexander T. Miller BS, Richard K. Gurgel MD. First published 16 March 2017, Laryngoscope Investigative Otolaryngology.
- How Can Hearing Loss Cause Dementia? Timothy D. Griffiths, Meher Lad, Sukhbinder Kumar, Emma Holmes, Bob McMurray, Eleanor A. Maguire, Alexander J. Billig, and William Sedley,Neuron. 2020 Nov 11; 108(3): 401–412.
- Association of Hearing Aids and Cochlear Implants with Cognitive Decline and Dementia – A Systematic Review and Meta-analysis. Brian Sheng Yep Yeo, MBBS1; Harris Jun Jie Muhammad Danial Song, MBBS1; Emma Min Shuen Toh, MBBS1; et al. December 5, 2022. JAMA Neurology